From aade6c0dfb46ff7ce7df0ed7a2ef15d2d3c47f05 Mon Sep 17 00:00:00 2001 From: Stefan Haberland Date: Tue, 10 May 2011 17:13:38 +0200 Subject: [S390] dasd: prevent IO error during reserve/release loop The termination of running CQR caused by reserve/release operations may lead to an IO error if reserve/release is done in a tight loop. Prevent this by increasing the retry counter after termination. Signed-off-by: Stefan Haberland Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 475e603fc584..86b6f1cc1b10 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -1742,11 +1742,20 @@ int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr) static inline int _dasd_term_running_cqr(struct dasd_device *device) { struct dasd_ccw_req *cqr; + int rc; if (list_empty(&device->ccw_queue)) return 0; cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist); - return device->discipline->term_IO(cqr); + rc = device->discipline->term_IO(cqr); + if (!rc) + /* + * CQR terminated because a more important request is pending. + * Undo decreasing of retry counter because this is + * not an error case. + */ + cqr->retries++; + return rc; } int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr) -- cgit v1.2.2